title: Expression and cellular localization of cyclooxygenases and prostaglandin E synthases in the hemorrhagic brain.
abstract: BACKGROUND
  Although cyclooxygenases (COX) and prostaglandin E synthases (PGES) have been implicated in ischemic stroke injury, little is known about their role in intracerebral hemorrhage (ICH)-induced brain damage. This study examines the expression and cellular localization of COX-1, COX-2, microsomal PGES-1 (mPGES-1), mPGES-2, and cytosolic PGES (cPGES) in mice that have undergone hemorrhagic brain injury.
  
  
  METHODS
  ICH was induced in C57BL/6 mice by intrastriatal injection of collagenase. Expression and cellular localization of COX-1, COX-2, mPGES-1, mPGES-2, and cPGES were examined by immunofluorescence staining.
  
  
  RESULTS
  In the hemorrhagic brain, COX-1, mPGES-2, and cPGES were expressed constitutively in neurons; COX-1 was also constitutively expressed in microglia. The immunoreactivity of COX-2 was increased in neurons and astrocytes surrounding blood vessels at 5 h and then tended to decrease in neurons and increase in astrocytes at 1 day. At 3 days after ICH, COX-2 was observed primarily in astrocytes but was absent in neurons. Interestingly, the immunoreactivity of mPGES-1 was increased in neurons in the ipsilateral cortex and astrocytes in the ipsilateral striatum at 1 day post-ICH; the immunoreactivity of astrocytic mPGES-1 further increased at 3 days.
  
  
  CONCLUSIONS
  Our data suggest that microglial COX-1, neuronal COX-2, and astrocytic COX-2 and mPGES-1 may work sequentially to affect ICH outcomes. These findings have implications for efforts to develop anti-inflammatory strategies that target COX/PGES pathways to reduce ICH-induced secondary brain damage.
authors.affiliation: Department of Anesthesiology/Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.forename: He
authors.initials: H
authors.lastname: Wu
authors.forename: Jessica
authors.initials: J
authors.lastname: Wang
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology / Q000201:enzymology* / Q000473:pathology*; D002543:Cerebral Hemorrhage / Q000201:enzymology* / Q000473:pathology*; D019746:Intramolecular Oxidoreductases / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D000071876:Prostaglandin-E Synthases; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D011451:Prostaglandin-Endoperoxide Synthases; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases; C000605865:Ptges protein, mouse; C000605866:Ptges2 protein, mouse